Connector and seal for defrost heater



Oct. 19, 1965 D. s. PHlLLlPs CONNECTOR AND SEAL FOR DEFROST HEATER Filed June 22, 1964 INVENTOR.

United States Patent O 3,212,287 CNNECTOR AND SEAL FOR DEFROST HEATER Donald S. Phillips, Evansville, Ind., assigner to Whirlpool Corporation, a corporation of Delaware Filed June 22, 1964, Ser. No. 376,878 8 Claims. (Cl. 62--276) This invention relates to refrigeration apparatus and in particular to means for providing an electrical connection and hermetic seal for a defrost heater which is located within the evaporator coil in such apparatus.

In refrigeration apparatus utilizing fluid refrigerants, a conventional structure for providing the low temperature portion of the apparatus comprises an evaporator defined by a serpentine tubular element. In the use of such evaporators, frost may accumulate on the external surfaces thereof. As such frost accumulation adversely affects the refrigeration capacity of the evaporator, it is desirable from time to time to remove the collected frost. One structure provided for this purpose is an electric heating wire arranged to extend through the passage defined by the tubular evaporator.

' A problem arises with such electric wire defrost means in that it is necessary to provide an electric connector and hermetic seal at the `opposite ends of the heater Wire which extends to exteriorly of the evaporator. Heretofore, no fully satisfactory connector has been provided for this purpose. The present invention comprehends an improved connector adapted to be carried by the evaporator to provide an electrical connection between the ends of the heater wire, a hermetic seal between the connector and the evaporator coil, and electrical supply means exteriorly of the evaporator.

Thus, a principal feature of the present invention is the provision of a new and improved refrigeration apparatus.

Another feature of the invention is the provision of a new and improved defrost heating structure for use in refrigeration apparatus.

A further feature of the invention is the provision of such a defrost heating structure including new and irnproved means for providing an electrical connection to the opposite ends of the heater wire.

Still another feature of the invention is the provisio yof such electrical connection means including a terminal extending through an insulating support, and means associated with the insulating means for providing a hermetically sealed closure of the evaporator while permitting electrical connection therethrough.

Other features and advantages will be apparent from the fol-lowing description taken in connection with the accompanying drawings, wherein:

FIGURE 1 is a schematic View illustrating the arrangement of an electrical defrost heater wire in an evaporator and means embodying the invention for connecting the opposite ends of the wire to electrical conductors exteriorly of the evaporator;

FIGURE 2 is an enlarged diametric section taken substantially along the line 2--2 of FIGURE 1, illustrating the connecting means in greater detail;

FIGURE 3 is a diametric section illustrating the method of assembly of the connecting means in `one end of the evaporator tube; and

FIGURE 4 is an end View of the connector.

In the exemplary embodiment of the invention as disclosed in the drawing, an electric heater wire is shown to extend longitudinally through a serpentine evaporator coil 11 and an accumulator 12 to adjacent the opposite ends 13 and 14 of the evaporator coil. The evaporator is associated with conventional refrigeration apparatus including a compressor 15, a condenser 16, and a capil- "ice lary 17 arranged to provide refrigerant to the evaporator wherein conventional expansion of the refrigerant causes the evaporator to -comprise a refrigerating structure.

The invention comprehends an improved connecting structure 18 for providing an electrical connection to the opposite ends of the heater wire as is more specifically illustrated in FIGURES 2 through 4. More specifically, the evaporator illustratively comprises a conventional n and tube evaporator structure. The ends 13 and 14 are similar, and, thus, in describing the connecting means 18 reference will be had to the tube end 14, it being understood that the connecting means associated with tube end 13 is identical thereto. As shown in FIGURE l, tube end 14 defines the inlet to the evaporator and tube end 13 defines the outlet thereto. In each of the tube ends, the refrigerant conduit connection is by means of a transverse tubular connection 19 opening into the evaporator passage 20 at a point spaced from the end of the tube.

The connecting structure 18 herein comprisees a cylindrical insulator 21 through which sealingly extends a connector bar 22 having a first end 23 disposed within the evaporator passage 2t) and a second end 24 disposed exteriorly thereof. The insulator may be formed of any suitable electrical insulating material, such as fused glass. The insulator is carried in a metal 1spool 25 having a radially outturned outer annular flange 26. As shown in FIGURE 3, the tube end 14 includes successively radially enlarged portion 27 and 28 and shoulders 29 and 30. As shown in FIGURE 2, an O-ring 31, which may be formed of a suitable sealing material, such as neoprene, is ycarried on fiange 26. In the made-up arrangement of the connecting structure, the distal end 32 of the tube end portion 28 is radially inturned and bears against the flange 26 to compress the O-ring 31 between the fiange and the shoulder 30, thereby sealing the flange to the tube end.

A conventional connector 33 is secured to the end of the heater wire 10 and the joint therebetween is sealed by a conventional molded seal 34 formed of a material such as Telion. The connector 33 is secured to 23 before connecting structure is sealed to tube end 14. The connector 33 includes an outer end 35 having a recess 36 in which is received the inner end 23 of the connector bar 22. The end portion 35 may be crimped tightly onto the connector bar portion 23 to assure a positive electrically conductive connection therebetween.

The external wire 37 may be provided with a connector 3S similar to connector 33, with the joint therebetween being sealed by a suitable seal 39. The outer end 24 of the connector is received in a recess 40 in the end of 41 of the connector 38. In the illustrated embodiment, the connector bar end 24 has a friction fit with the connector in recess 4tl so as to provide a readily disconnectable, positive electrically conductive connection to the wire 37.

In assembling the connecting means 18, firstly a connector 33 is secured to each of the opposite ends of the heater wire 10 and sealed thereto by means of seals 34. The heater wire is then disposed within the serpentine tube 11 with the oposite ends thereof disposed adjacent ends 13 and 14 of the tube.

The O-ring 31 is next installed on the flange 26 of the spool 25 and the end 23 of the connector bar 22 is inserted into the recess 36 of the connector 33. The wire 10 is preferably of sufficient length to permit a suicient withdrawal thereof from the tube to allow connection of the connector 33 to the connector bar.

The end portion 35 of the connector 33 is then crimped tightly onto the connector bar portion 23 to assure a positive electrical connection therebetween. The connecting means 18 is then moved into the space dened by the tube portions 27 and 28 until O-ring 31 abuts the shoulder 30. Distal end 32 of the tube is then inturned, as by rolling, against flange 26 of the spool 25 to compress the O-ring sealingly between the flange 26 and the shoulder 30 thereby hermetically closing the end 14 of the tube 11.

The wire 37 is connected to the outwardly projecting end 24 of the connector bar 22 as discussed above by means of the connector 38 having a friction fit therebetween.

While I have shown and described one embodiment of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as defined in the appended claims.

'The embodiment of the invention in which an exclusive property or privilege is claimed is defined as follows:

1. Refrigeration apparatus comprising:

means defining a refrigerant flow passage having an opening;

a defrost wire in said passage and having an end adjacent said opening;

closure means sealingly closing said opening;

a connector sealingly carried by said closure and having an inner end exposed to said passage;

means fixedly connecting said inner end of said connector to said defrost wire end; and

means for connecting an electrical conductor externally of said passage to said connector for energizing said defrost wire.

2. Refrigeration apparatus comprising:

tubular means defining a refrigerant flow passage having an end defining an axial opening;

a defrost wire in said passage and having an end adjacent said opening;

closure means for sealingly closing said opening;

a connector sealingly carried by said closure and having an inner end exposed to said passage and an outer end exposed to exteriorly of said tubular means; and

means fixedly connecting said inner end of said connector to said defrost wire end.

3. The refrigeration apparatus of claim 2 wherein the closure means includes an annular flange and said end of the tubular means includes means defining a radially inwardly opening groove receiving said flange and retaining said flange against axial outward movement.

4. The refrigeration apparatus of claim 2 wherein the closure means includes an annular flange and said end of the tubular means includes means defining a radially inwardly opening groove receiving said flange and retaining said fiange against axial outward movement, and an annular seal in said annular recess for sealing said flange to said tubular means end.

5. The refrigerant apparatus of claim 2 wherein sai-d tubular means end includes a radially outwardly extending shoulder, a cylindrical portion extending axially outwardly from -said shoulder, and an annular inturned distal end extending radially inwardly from the outer end of said cylindrical portion, and said closure means includes annular means disposed between said shoulder and said distal end and including sealing means for sealing the closure to said shoulder.

6. The refrigeration apparatus of claim 2 wherein the closure means comprises a cylindrical body of insulating material, a spool support having a tubular portion and an outturned end flange at one end thereof, and a sealing ring concentrically surrounding said tubular portion and axially engaging said flange, said connector extending Isealingly axially through said cylindrical insulating member and having opposite ends projecting outwardly therefrom.

7. The refrigeration apparatus of claim 2 wherein the tubular means includes a conduit opening into said refrigerant flow passage at said end.

8. A connecting structure comprising:

a tubular housing member having an outer end portion defining a pair of spaced confronting inner and outer annular shoulders;

a cylindrical body of insulating material;

an electrical conductor extending coaxially through said body and having opposite ends projecting outwardly therefrom;

a spool support concentrically surrounding the insulating body and having a tubular portion extending substantially the length of the insulating body and an outturned flange at one end; and

a sealing ring juxtaposed to said flange and concentrically `spaced radially from said tubular portion, said insulating body and spool support being disposed fully within said housing end portion with said flange outermost and abutting said outer shoulder of the housing, and said sealing ring disposed inwardly of said flange and being sealingly compressed between said flange and said inner shoulder of the housing, the outer diameter of said tubular portion being slightly smaller than the inner diameter of `said end portion of the tubular housing.

References Cited by the Examiner UNITED STATES PATENTS 2,138,660 11/38 Mann 174-152 2,450,780 10/48 Bucklen 174-152 2,503,429 4/50 Ziegler 174-152 2,705,874 4/55 Binder 62-276 2,755,371 7/56 Jackson 62-276 2,877,630 3/59 Schultz 62-276 WILLIAM I. WYE, Primary Examiner, 

1. REFRIGERATION APPARATUS COMPRISING: MEANS DEFINING A REFRIGERANT FLOW PASSAGE HAVING AN OPENING; A DEFROST WIRE IN SAID PASSAGE AND HAVING AN END ADJACENT SAID OPENING; CLOSURE MEANS SEALINGLY CLOSING SAID OPENING; A CONNECTOR SEALINGLY CARRIED BY SAID CLOSURE AND HAVING AN INNER END EXPOSED TO SAID PASSAGE; MEANS FIXEDLY CONNECTING SAID INNER END OF SAID CONNECTOR TO SAID DEFROST WIRE END; AND MEANS FOR CONNECTING AN ELECTREICAL CONDUCTOR EXTERNALLY OF SAID PASSAGE TO SAID CONNECTOR FOR ENERGIZING SAID DEFROST WIRE. 